(1) Field of the Invention
The present invention relates to the field of loudspeakers and, in particular, to a high power loudspeaker system, a loudspeaker and a loudspeaker horn providing a predefined coverage pattern fed by an optimally shaped wave front created by an array of multiple drivers.
(2) Description of Related Art
In the field of generating and distributing acoustic energy and in particular where the acoustic energy is to be received and recognized by a large number of listeners who are distributed over a given area, many loudspeaker arrangements use multiple horns. Horns generally have an expanding cross-sectional area moving away from the acoustic source such that, in general terms, the horn is used to direct the acoustical energy along the axis of the horn.
Horns have very specific directional acoustical energy distribution characteristics. These characteristics are utilized in applications where the listeners are within a predetermined area relative to the arrangement of the horns. Such applications include but are not limited to open and closed sports arenas, for example.
One conventional directional loudspeaker is disclosed in U.S. Pat. No. 4,344,504 issued to Bruce Howze on Aug. 17, 1982. In this patent, a loudspeaker is disclosed to allegedly have uniform horizontal sound dispersion characteristics in a design angle while having minimal vertical sound dispersion. It utilizes multiple sound energy sources which form an elongated line source of sound energy, and a wave guide having an elongated input portion coextensive with the elongated line source. The planar side walls of the wave guide minimize sound dispersion in a direction parallel to the line source while expanding the sound dispersion in a direction perpendicular to the axis of the line source, thereby differentiating the sound dispersion between vertical and horizontal planes.
In the Howze directional loudspeaker, the line source is formed in a single plane and the mouths of the horns are also in a single plane.
The Howze directional loudspeaker suffers from a number of drawbacks. For instance, vertical sound dispersion is not constant with frequency over the intended bandwidth. Additionally, vertical sound dispersion is preferred in some environments, thus making the Howze directional loudspeaker inappropriate.
It is an object of the present invention to provide a tightly controlled energy distribution pattern in a horizontal plane over a broad frequency range.
It is another object of the present invention to provide a tightly controlled energy distribution pattern in a vertical plane over a broad frequency range.
It is still another object of the present invention to significantly increase the amount of acoustic energy in a defined area, as compared to a commonly used single driver horn.
It is still yet another object of the present invention to provide a coherent acoustical wave front that mimics a single idealized point source with a defined energy distribution pattern.
It is still yet a further object of the present invention to eliminate or ameliorate to insignificance the interference patterns caused by multiple time arrivals in horn arrangements which are specifically designed to increase the energy density over a defined area by overlap of multiple single driver horn patterns on the defined area.
It is still yet another object of the present invention to optimize the amount of acoustical energy delivered by an array of multiple driver horns to a defined area by adjustment of the vertical and/or horizontal coverage angles of the individual multiple driver horns in the array.
It is yet another object of the present invention to optimize the amount of acoustical energy delivered by an array of multiple driver horns to a defined area by adjustment of the vertical and/or horizontal angles of individual vanes located in an area in front of the mouth of a throat section or mouths of the throat sections.
These and other objects and advantages are achieved by providing a horn including a plurality of electroacoustical drivers for generating sound waves over a range of frequencies and each having a sound outlet port; a plurality of throat sections each having an axis and each extending from an inlet to a mouth, wherein inlet of respective throat sections of the plurality of throat sections are acoustically coupled to the outlet ports of respective drivers of the plurality of drivers, whereby the mouths of the plurality of throat sections are disposed on an arcuate array in a first plane.
The present invention may also be embodied in a loudspeaker including a housing and at least one of the above described inventive horns.
The present invention may further be embodied in a loudspeaker system including a plurality of loudspeakers, at least one of the plurality of loudspeakers having a housing and at least one inventive horn. Further, the loudspeaker system may include a plurality of loudspeakers in the form of an array wherein at least one loudspeaker is at an angle (greater than 0xc2x0, and less than 180xc2x0) relative to an adjacent loudspeaker.